Video communication systems span a variety of applications. One such application is videoconferencing. Videoconferencing typically involves the real-time sharing of video along with audio, graphics and/or data information between two or more terminals over a communications channel. A videoconferencing session may involve merely a video-enabled telephone call between two friends or, in a more complex application, involve a multi-way call among corporate boardrooms with advanced camera control and with sharing of data applications such as word processors and spreadsheets and using ISDN digital lines or T1 lines for communication.
Videoconferencing technology has been evolving vary rapidly. The evolution began with a number of proprietary products, offered by various vendors and communicatively incompatible with each other. As the demand for equipment compatibility grew, vendors and scientific experts began to cooperate and, through a standards body such as the International Telecommunications Union (ITU), industry standards have been and are being adopted. This has typically involved the effort of an industry-wide consortium, such as the International Multimedia Teleconferencing Consortium (IMTC), to iron out implementation details of the standards, agree on the interpretation of sections of the standards that are unclear, and test each of the vendor's products against those provided by other vendors.
Once a baseline level of interoperability has been established, the vendors proceed to bring their standards-compliant products to market, and continue to add their own features that, while preserving standards compliance, differentiate their products from those of other vendors in order to gain competitive advantage.
Standards bodies such as the ITU strive to allow as much flexibility as possible in their standards. This allows vendors to use their research and product development resources to improve their products in particular and the videoconferencing communication in general. A few examples of vendor-specific features are the "look-and-feel" of the product, the graphic-user interface, pre- and post-processing to improve video quality, and audio echo-cancellation to improve the quality of full-duplex conversation.
The state of the art in videoconferencing has been continually advancing, and organizations such as the ITU are at the forefront of the videoconferencing research. The ITU issues revisions and upgrades to its standards at regular intervals, usually maintaining backwards compatibility with the original standard, but providing significant advantages in terms of both features and level of performance with the revision. With each revision, the cycle of testing among vendors and the emergence of vendor-specific features repeats.
Accordingly, any given videoconferencing product becomes obsolete if it is not upgraded according to the progression of the state of the art in videoconferencing technology. The cost of such upgrades can be high, particularly if the upgrades require a vendor to swap equipment or send technicians to customer sites. The upgrade cost can be especially prohibitive in the mass consumer market where the customer is extremely price sensitive, and where upgrading of equipment via on-site visits by vendors is virtually impossible.
Recent developments in the videoconferencing industry has made the mass consumer market largely accessible to vendors for the first time. One such development is the ITU's H.324 standard, which specifies a standard for videoconferencing over ordinary "plain old telephone service" (POTS) phone lines. The H.324 standard has lead to a number of small videophone products that appeal to the mass consumer, at costs moving toward less than a few hundred dollars. However, the problem of obsolescence of these products, and the potential high cost of upgrades, is substantial.